Cooling devices for electron tubes



July 14, 1959 G. J. AGULE COOLING DEVICES FOR ELECTRON-TUBES Filed June 21, 1955 FIG. 2

IFIG.3

FIG.4

INVENTOR.

GEORGE J. AGULE FIG. I I BY COOLING DEVICES FOR ELECTRON TUBES George J. Agule, Stamford, Conn, assignor to Machlett Laboratories, Incorporated, Springdale, Conn, a corporation of Connecticut Application June 21, 1955, Serial No. 517,005

Claims. (Cl. 257-250) This invention relates to cooling devices for electron tubes and has particular reference to novel water cooling means for cooling the anodes of electron tubes such as power tubes used for transmission purposes, dielectric and induction heating.

Many different systems for cooling electron tube andoes are disclosed by the prior art and the type believed to be most satisfactory from manufacturing and efliciency standpoints consists of a jacket which fits over and encloses an anode, with water being forced into the space between the jacket and the anode for cooling purposes. A common practice in manufacturing such cooling systems has been to form the jacket as an integral part of the tube with inlet and outlet openings for permitting circulation of the water over the external surface of the anode. In some cases the end of the jacket is open and requires that a removable cap be provided so that the system will be totally enclosed to permit eflicient distribution of the water over the anode during operation of the tube.

With such a construction it is apparent that by forming the Water jacket as an integral part of a tube, the problems involved in manufacture are relatively complicated and the final tube cost is relatively high. In addition to these disadvantages, high maintenance costs result when a tube is discarded after being worn out or damaged due to the fact that the cooling system, which must also be discarded, is generally still usable and capable of eflicient operation.

To overcome the disadvantages found in integrally formed water jackets, attempts have been made to provide separate water jackets which are mounted over anodes and sealed thereto by O-ring gaskets and locked in position on the anodes by movable members such as threaded rings, cams or pins, or by intricate or interlocking members and the like. In such gasketed constructions, damage from mechanical shock can occur during mounting of a tube in a jacket when forcing the tube into a gasket and against a stop usually provided for axial positioning of the tube. Furthermore, with this type of construction, the movable or interfitting parts often become jammed, stuck or otherwise troublesome. Another disadvantage is that should a movable connection become loosened and a jacket become accidently disconnected from the tube during operation, the water, which is generally under considerable pressure, will be forced out of the jacket with possible disastrous results. Such devices are also sometimes difficult to assemble, such as when aligning threaded parts. In addition, constructions of this type are generally more expensive to manufacture due to the fact that the intricate interfitting and movable parts must be accurately formed and therefore require a relatively great degree of skill to manufacture.

The present invention is directed toward overcoming the disadvantages of prior art water cooling devices of the above character by the provision of an improved removable water jacket which embodies no movable parts, which is easily and quickly assembled in position of use with an anode by a single simple operation, which cannited States Patent 0 ice not be removed when water is being forced through it under pressure, and which is relatively inexpensive to manufacture.

Accordingly, it is a primary object of this invention to provide a water cooling device for the anode of an electron tube which comprises a jacket adapted to be assembled with the anode and locked in position of use by means of a fixed locking member which is carried by a supporting portion of the tube and which engages interfitting means formed on the jacket.

Another object is to provide a water jacket with a slot for receiving an interfitting pin or lug on the tube, which slot is angled so that a limited amount of rotation of the tube about its longitudinal axis will cause the tube to automatically align itself in the jacket and to be locked in position therein.

Another object is to provide a jacket of the above character with an open-ended slot having at its extreme inner end a recess in which the locking member is adapted to reside, whereby when water is forced under pressure into the jacket the locking member will tend to become more firmly held in position and the tube prevented from accidentally becoming disconnected from the jacket.

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawing, in which Fig. 1 is a front elevational view partly in axial section of an electron tube carrying a water jacket embodying a preferred form of the invention;

Fig. 2 is a top plan view of the water jacket;

Fig. 3 is a side elevational view of a portion of the water jacket shown in Fig. 1 showing the locking means; and

Fig. 4 is an axial sectional view of the water jacket.

Referring more particularly to the drawing, wherein like characters of reference designate like parts throughout the several views, one form of electron tube, with which a cooling system embodying the invention may be used, comprises an anode 10 which is in the form of a deep cylindrical cup of highly conductive material such as copper. Into the anode 10 extends the filament structure 11 and grid assembly 12. The grid assembly 12 includes a cage formed with a number of support rods 13 axially aligned and arranged in the form of a cylinder. At one end the grid support rods 13 are attached to a metal disk 14 and a grid wire 15 is helically wound around the rods 13.

The other ends of the grid support rods 13 are attached to the grid support ring on terminal 16 by means such as clearly shown and described in my US. Patent No. 2,707,757, issued May 3, 1955.

The filament structure 11 also includes a cage formed of a number of wires 17, preferably of tungsten, extending in an axial direction with cylindrical configuration. The lower ends of the filament wires 17 are bent inwards and spaced around a spool 18 and a relatively fine wire 19 is wound around the ends of the wires and soldered or otherwise secured so as to form a joint of good electrical conductivity between the ends of all the filament wires.

The other ends of the filament wires are attached to support rods 20 by clips 21 and the rods 20 are alternately connected to filament terminals 22 and 23 by means such as shown and described in the aforementioned patent. The filament cage is thus suspended within the grid cage and both are coaxial with the anode 10.

The anode 10 has one end extending through an annular ring seal 24 and is circumferentially connected to the inner periphery of the seal 24. The seal 24 includes a flanged portion 25 which functions as the anode terminal.

A dielectric bulb 26 forms a gas-tight non-conductive enclosure connecting the anode terminal 25 to the grid terminal 16, a similar bulb 27 encloses the space bu tween the grid terminal 16 and filament terminal 23, while a third similar bulb 23 encloses the space between the filament terminals 2.3 and 22.

A cooling device 29 is employed for dissipating heat from the anode it) during operation of the tube and comprises an outer cylindrical or tubular jacket 30 which has a coaxial inner cylindrical or tubular baflle 31. The lower ends of the baffie 31 and jacket 3% are connected and sealed by a base 32 which comprises two spaced annular portion 3334 joined at their inner peripheries by a tubular portion 35. Upper annular portion 33 is at tached throughout its outer peripheral edge to the adjacent end of the baffle 31 while the lower annular portion 34 is of slightly larger diameter and is sealed along its periphery to the end of the jacket 30. Thus there is provided a chamber 36 between the annular portions 3334 which is in communication with the space 37 between the jacket 34 and baffie 31.

The upper end of the exposed portion of the anode has a circumferential ring 38 soldered or otherwise sealed thereto. The ring 38 is adapted, when the cooling device 29 is assembled with the tube, to snugly engage an O-ring gasket 39 which is carried within a groove 40 formed circumferentially in the inner surface of the jacket 30. The gasket 39 extends outwardly of the groove 4% beyond the plane of the inner surface of the jacket 30 so that a water-tight seal is formed between the jacket 30 and the ring 38. The baffie 31 terminates below the seal and so does not interfere with assembly of the cooling device 29 on the anode 10.

Means is provided for removably locking the cooling device in assembled relation with the anode and com prises connections similar to so-called bayonet connections. The jacket 3i is provided in its upper end with a plurality of slots 41 which are angled laterally and downwardly as shown in Fig. 3. A plurality of pins 42 corresponding in number to the slots 41 are fixedly mounted in the ring 38 carried by the anode it) and are adapted to be simultaneously inserted in respective slots 41.

To assemble the cooling device 29 with the anode it), it is merely necessary to insert the anode it) within the baffie 3i to an extent where the pins 42 will engage the end surface 43 of the jacket 30. Then by rotating the tube about its longitudinal axis in a clockwise direction, the pins 42 will engage the slots 41. Continued rotation together with inward pressure will cause the pins to follow the slots 41 to a point where they will move into notches 44 provided therefore in the upper sides of the end portions of the slots. A coiled spring 45 is positioned in the bottom of the baflle 3i and is adapted to engage the adjacent end of the anode if to yieldably urge the tube in an upward axial direction. in this manner the pins 42 are retained within the notches 44.

The end surface 43 of the jacket 30 is also provided with raised portions 46 immediately above the slots 41. The ends of the raised portions 46 form stops 47 against which the pins 42 will abut if an attempt is made to assemble the device by rotating the tube accidentally in a counterclockwise direction or if overtravel occurs when removing the tube from the jacket. Thus the pins as will not fall into the slots 51 with consequent undcsirable jarring or shocking of the tube. The inner peripheral edge of the jacket 3i) is also beveled as indicated by numeral 48 so that the device can more easily and quickly be mounted over the ring 38.

After the device is assembled with the anode it the anode is cooled by introducing a flow of coolant such as water over the external surface of the anode. For this purpose an inlet 49 is provided in the lower end of the cooling device 29. The inlet 49 is preferably a short conduit 50 Which is mounted at one end Within the central opening formed by the tubular portion 35 of the base 32. The conduit 49 may be connected in any suitable manner to a source of coolant. An outlet 51 is similarly formed by an opening 52 in the lower annular portion 34 of the base in which is located a short conduit 53 which may be suitably connected to a tank or reservoir. Water introduced into the chamber 54 be tween the anode 1d and baffie 31 will flow around the anode, filling the bafiie and overflowing its top into the chamber 37 between the bafille 31 and jacket 30, and thence through chamber 36 and out through outlet 51.

Referring to Fig. 4 it will be noted that the inner wall of the baffie 31 is provided with a plurality of helices 55 which are preferably in the form of wires permanently afiixed to the wall as by soldering. The thickness of the wires is substantially equal to the width of the portions of the chamber 54 between the anode 1i) and bafiie 31. In this way spiral channels are formed for directing the water along controlled paths over the surface of the anode for more efficient cooling. Since the spacing between the anode and battle is relatively small and the water is introduced under relatively high pressure, there is produced a high velocity stream adjacent the surface to be cooled.

It is apparent from the foregoing description that an improved cooling device has been produced for dissipating heat from an anode of an electron tube in a simple and eificient manner, and that the device can be easily, quickly and efficiently assembled in position of use with an electron tube, in accordance with the objects of this invention.

It is to be understood, however, that while the novel features of the invention have been shown and described and are pointed out in the annexed claims, various omissions, substitutions and changes in the construction and arrangement of parts shown and described may be made by those skilled in the art without departing from the spirit of the invention. Therefore, it is to be understood that all matter shown or described is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. A device for securing an enclosing open-ended jacket to an anode of an electron tube comprising a slot in the jacket extending from the open end thereof and angled in one direction inwardly and laterally from said open end, a pin carried by the anode and adapted to be retained within the angled slot to retain the jacket and anode in assembled relation, and stop means on the open end of the jacket comprising a projection adjacent the open end of the slot and on the side thereof corresponding to the direction in which the slot is laterally inclined.

2. A device as set forth in claim 1 wherein the closed end of the slot is provided with a notch extending in a direction toward the open end of the jacket for rereiving the pin when the jacket and anode are assembled, and spring means is provided between the anode and jacket for yieldably urging the jacket axially in a direction away from the anode to retain the pin and notch in engaged relation.

3. A device for securing a hollow open-ended water jacket in sealed enclosing relation to an anode of an electron discharge device comprising an annular circumferential ring carried on the outer surface of the anode adjacent one end thereof and adapted to receive thereover the open end of the jacket, a plurality of radially extending pins disposed at spaced intervals in the ring, a corresponding number of slots in the jacket extending from the open end thereof, each slot being angled in one direction inwardly and laterally from the open end, said open end of the jacket having a relatively smooth end surface for engagement by and for guiding the pins into respective slots upon rotation of the anode with respect to the jacket in one direction, the end surface further having stop means adjacent each slot and on the sides thereof corresponding to the directions in which the slots are laterally inclined for preventing the pins from engaging the slots when the jacket is rotated in the opposite direction.

4. A device as set forth in claim 3 wherein the closed ends of the slots are provided with notches extending in a direction toward the open end of the jacket, and resilient means is provided between the anode and jacket for yieldably urging the jacket axially in a direction away from the anode to retain the pins within the notches when the jacket is assembled with the anode.

5. A device as set forth in claim 3 wherein the stop means each comprise an integral portion of the end of the jacket which projects outwardly beyond the plane of the major portion of the end surface.

References Cited in the file of this patent UNITED STATES PATENTS 

